1. Field of the Invention
This invention relates generally to the irrigation of soil or other growing medium for potted plants, and specifically to a closed irrigation system for container grown plants, preferably for large scale plant culture such as greenhouses, plant nurseries and florist shops, to conserve water, to increase plant irrigation efficiency, and to reduce human labor time involved in keeping the plants properly watered.
2. Description of the Prior Art
Sub-irrigation of soil in containers for container grown plants using systems where the irrigation water is recycled is known in the prior art. My U.S. Pat. No. 4,211,037 issued Jul. 8, 1980 and my U.S. Pat. No. 4,245,434 issued Jan. 20, 1981 disclose systems wherein the sub-irrigation of soil is accomplished through use of a return pipe or feeder tubes and gravity across a large bed using a capillary sheet which comprises a wettable plastic sheet from 11/2 to 2 mils in thickness made of polyethylene commonly manufactured in a continuous roll. In general the capillary sheet includes a multiplicity of substantially evenly spaced capillary openings. My U.S. Pat. No. 4,211,037 discloses the construction of the capillary sheet. The capillary hole size for desirable functioning utility may be produced from prongs having diameters which are 0.045". The spacings between the openings in the capillary sheet for practical purposes are regularly spaced approximately one-half inch apart. Although the systems shown in my U.S. patents cited above provide for distribution to supply plants through holes in the bottom of containers and recycled use of irrigating water, the present invention provides improvements in supply water distribution and reuse in a closed system. The term water and liquid used throughout includes all water and aqueous liquids containing plant nutrients. My present invention uses an improved liquid transfer bed in a bench to supply a plurality of conventional potted plants with water and to capture efficiently excess water for reuse. A network of wicks strategically located throughout the bench quickly and efficiently uniformly distribute and transfer excess water from the bench into a closed conduit system which prevents evaporation and prevents outside contamination of the irrigating liquids. My new irrigating system is designed for commercial production or residential environment.